This invention relates generally to chuck tools, and more particularly to an improved chuck especially constructed to accommodate threaded fasteners having a head or the like defining an eye formation, and which normally is not adaptable for direct engagement with conventional fastener drive elements.
1. Field of the Invention
The majority of threaded fasteners are adapted to be applied or removed from an associated material or work piece element by either a hand or power tool having a well known drive element adapted to mate with one or more conventional formations on the head of the fastener. In the case of fastener heads having a female Phillips or slotted/straight formation, it is known to provide drive bits having tips presenting a mating, male Phillips or straight blade configuration. In this manner, such drive bits may be utilized with either a hand or power mechanism to apply or remove these types of fasteners, be they screws or bolts.
A problem exists, however, when attempting to employ a tool to carry out the application or removal of specialized threaded fasteners such as screw-eye lag screws or bolts. Obviously, a slotted or Phillips drive bit would be of no help in engaging the substantially circular and planar configuration of the eye portion of such fasteners, nor can the eye formation be directly captured by the either the chuck of a drill device or the stub of an impact wrench.
Accordingly, it will be appreciated that a need exists for a tool that may be used with either a hand or power drill as well as an impact wrench in order to facilitate the ready application or removal of a threaded fastener having an eye formation on its head. Such a tool should comprise simple component(s) permitting of quick and easy attachment relative the intended fastener, and allow for the trans-mission of torque from the associated driving force, in a positive manner insuring of accurate, controlled assembly or disassembly of the fastener relative the material or article engaging its threads.
2. Description of the Related Art
An early example of a tool specifically adapted to facilitate the application and removal of screw eye fasteners will be found in U.S. Pat. No. 882,937 issued to Fegley on Mar. 24, 1908, and which includes a transversely slotted head engageable about a portion of the eye of a fastener. A pair of axially displaceable spring jaws, shiftable to bear upon the shank of the fastener, assist in retaining the fastener relative the tool while several other elements are called for to complete the tool assembly. This construction is quite unlike the present invention wherein no more than two very sturdy components are called for and which combine to provide enhanced stabilization of the eye of a fastener by engaging same along pairs of opposed faces such that positive driving forces are transmitted thereto.
U.S. Pat. No. 3,228,269 issued on Jan. 11, 1966, to Heyer relates to a driving tool for door stop elements, particularly those including a coiled spring section intermediate the shank and proposes an elongate body having a forked end and into which the door stop is laterally inserted with the threaded end thereof projecting through the forked end. In one embodiment, a wrench may be applied to the tool with rotary motion being transmitted by engagement of flats on the door stop by flat surfaces within the tool. The instant arrangement differs from the Heyer device in that laterally opposed surfaces of an eye formation on a threaded fastener are initially engaged by opposite recesses in an outer sleeve, following which a driver insert is slipped into the sleeve and includes transverse semicircular segments straddling and engaging opposite faces of the screw eye formation.
A two-part drive tool for lag fasteners is shown in U.S. Pat. No. 4,724,731 issued to Onofrio on Feb. 6, 1988, and depicts an inner drive element having a transverse slot into which the head and shank of a fastener is received while a plain sleeve is adapted to slide over the drive element and serves to strengthen the bifurcated portion thereof. The current improvement departs from the Onofrio device in that enlarged eye formation lag screws are being operated upon, rather than flattened eye lag screws and thus provision is made to accommodate the enlarged diameter thereof. Additionally, the present outer sleeve offers a slotted base plate to axially align the fastener shank, as well as opposed recesses stabilizing opposite edges of the enlarged fastener eye formation.
A tool for specifically driving eye screws will be found in U.S. Pat. No. 5,335,569 issued to Rowley on Aug. 9, 1994, and includes an elongate body provided with a circular recess accommodating screw eyes of varying diameters while the shank of the fastener reposes within an adjacent semicylindrical channel. An upstanding post within the recess fits within the fastener eye and its position may be adjustable. During operation of the tool, a slidable cover overlies the fastener eye within the recess to retain the fastener in place. Unlike the Rowley tool, the current apparatus is devoid of a multitude of relatively finely machined components and offers firm stabilization of an eye fastener by providing two sets of engaging surfaces respectively bearing upon two opposed surfaces of fastener eyes.
Various alternative tool socket formations are exhibited in U.S. Design Pat. Nos. Des. 160,267, Des. 195,736 and Des. 274,881 respectively issued to McCammon et al. on Sep. 26, 1950, McManus on Jul. 23, 1963, and Wilsey on Jul. 31, 1984. The tools of McCammon et al. and Wilsey appear to accommodate hexagonal work pieces of a specific size while the McManus device presents a transversely slotted member adapted to engage valves.
None of the above inventions and patents, taken either single or in any combination, is seen to even remotely suggest or describe the instant invention as claimed herein.